Hi, following is a part of schematic (please see attachment). 555 is a delay off timer. When power is supplied to timer it energizes the Relay for 10 seconds. Timer itself and other parts are working fine. Yellow 9V supply line is always available to circuit. Red supply line is occasionally available. The goal was to turn OFF the timer circuit when the RED supply is present and vice versa. But here PNP transistor is not working properly. I thought it would cut off the timers power; when RED supply is present by turning its base high but it is not working as it was supposed to work. Probably Ive selected the wrong values of biasing resisters. Ive tried different values of base resisters. Sorry, Im not expert of electronics and always need suggestions. Some body please trace out the fault. Where I am going wrong? Thanks and regards.
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